February 2012 Archive for In the Shop

As a farm machinery mechanic and writer, Dan brings a hands-on approach that only a pro can muster. Along with his In the Shop blog, Dan writes a column by the same name as well as the Shop Series for Farm Journal magazine. Always providing practical information, he is a master at tackling technical topics and making them easy for all of our readers to understand. He and his wife, Becky, live near Bouton, Iowa.

In this month's Farm Journal Magazine I authored a story that looks at the way we use WD-40, duct tape, zip ties and Vise-Grips to fix just about anything that needs to be fixed on farms. Mike McGuire from down in Munday, Texas, emailed me a great tip on modifying a pair of Vise-Grips to help remove seals. He says to:

"Remove the adjusting screw from the Vice-Grips and replace it with a long bolt or all-thread with a nut and washer of the same size with a piece of cold rolled steel shaft with a hole drilled through it for a slide hammer. To remove a seal, drill a small hole in the seal, thread a self-tapping screw into the seal, leaving enough sticking out to attach the Vice-Grips. The slide hammer will make quick work of removing the seal."

Great idea! I've used a self-tapping screw and Vise-Grips to pry out seals, but I really like the idea of creating a Vise-Grip slide hammer. That's a tool that would be handy for more than removing seals.

Back in the '60s, my father and uncle each took their 450 Farmall tractors to the local dealership for an overhaul. Not at the same time, but within a few months of each other. Later that year they compared bills, and found a significant difference in price. Not surprisingly, intense discussions with the dealership ensued shortly after that discovery. The dealer explained his side of the story, compensations were offered, and you can be certain every bill was carefully checked, line-by-line, item-by-item, whenever repair work was done in the future.

I now understand how two bills for nearly identical repairs could vary by a hundred dollars or more. Yes, many dealerships have "flat rates" that standardize the cost of common repairs, but there are variables in every repair job that can increase or decrease the final cost, compared to flat rate. If a bolt breaks off and has to be tapped out--that's extra time. If the machine is so filthy dirty that the mechanic can't make repairs without risk of contaminating the oil, fuel or air system and has to be washed prior to repairs--that's extra time. If a tractor has a loader, or a planter has a liquid fertilizer system that interferes with normal access to components on the basic machine--that's extra time. And at equipment dealerships, time IS money.

There may also be extra costs associated with parts that are used during repairs. Some mechanics routinely replace every nut, bolt and fastener during a repair. Other mechanics evaluate the condition of nuts and bolts and re-use them if they're in non-critical locations. Some mechanics drain and re-use hydraulic oil or antifreeze with the customer's permission. Other mechanics have an "all-new" policy with fluids to eliminate the risk of contaminating newly repaired components.

It pays to read every line of a repair bill, and nobody should be offended if you ask questions about specific charges or costs. Looking back, I now understand both sides of the situation when Dad and Uncle Francis went to war with the local dealership over differences in bills for "identical" repair jobs. Nobody was completely wrong, but it was the dealership's duty as a reputable business to make sure its customers were satisfied and comfortable with their billing.

Scott, our technology specialist, taught me a nifty trick today. I was working with a machine that has a touch-screen display in it, and the screen often would barely react when I poked it with my finger to change a setting. Sometimes it wouldn't work at all--just stayed frozen on the same image no matter how much I poked and prodded. And I eventually poked and prodded it pretty hard.

I gave Scott a call, and he said to stick the corner of a business card carefully between the surface of the screen and the edge of the screen's housing, and carefully run it around the entire perimeter. He said dirt, dust and debris often gets wedged between the face of the screen and the housing, which applies pressure to the screen at that point. The display thinks somebody is holding their finger against the screen, which causes the problems I was experiencing.

Sure enough, there were two spots, one on the right side and one along the bottom edge, where the business card found teeny little bits of debris wedged between the face of the screen and the housing. I did a little gently prying, used a can of "air in a can" to blow things out, and the display now works just fine.

It bothered me to admit in my last blog that planter gauge wheel tires were getting the best of me. I'm going to salvage my pride by offering tips that have allowed me to emerge victorious from efforts to efficiently replace the small rubber tires on planter closing wheels.

Modern rubber tires on planter closing wheels, like the aforementioned gauge wheel tires, aren't as easy to change as their ancestors. I'm suspicious manufacturers have toughened their rubber compounds to reduce wear in no-till situations. It seems to be more of a challenge to change closing wheel tires now than it used to be. But if I have time and foresight, it helps to soften the tires by laying them in the sun for half and hour, or, if you're in a rush, laying them in front of the hot air blowing from a pickup truck's heating duct. If you've got access to hot water, soaking them in a bucket filled with hot water works nice, too.

Then use either soapy water or some sort of lubricant to speed the process as you use flat-blade screwdrivers or your fingertips to lever the side of the tire into the appropriate grooves in the wheel-half, before bolting the two halves together. It's still not as easy as I remember it from years ago, but I seem to remember being able to grab a rubber closing wheel tire in both my hands and stretch it like a rubber band.

I can't do that anymore. Either the new tires are lots tougher and less resistant to stretching, or...

Here's the deal: back when I was a hired man on a large grain and livestock farm, I did all the service work on the field equipment. I changed a lot of gauge wheel tires on planters. It was never especially easy, but I could get the job done in about 15 minutes per tire.

For the past few years I've been quietly suffering in embarrassment because I can't seem to successfully, efficiently change tires on gauge wheels any more. I was beginning to think age was seriously affecting my ability to do my job, until today another mechanic came up, exasperated, and declared he was never going to agree to replace another planter gauge wheel tire.

We talked it over, compared notes, compared various tricks and strategies we've tried, and in the end agreed that something has changed over the past few years to make it very difficult to change tires on planter gauge wheels. It used to be we could unbolt the split gauge wheel rim, remove the old tire, lube up the bead on the new tire, put the new tire between the rim halves, then stomp or press the split rim back together to install the tire.

Not anymore. No amount of lubrication, stomping or hydraulic pressing seems to easily press a tire onto the halves of the rim. Note that I said, "easily." If we mess around long enough, we can eventually get the tire installed. But it can easily take a half hour per tire.

On top of that, we've noticed that even after we manage to get a new tire mounted on a used gauge wheel rim, about 1/3 of the time the gauge wheel bearing that is sandwiched between the halves of the rim gets "cocked" during the assembly process, causing the wheel to wobble or run crooked. That makes it impossible to get and maintain the proper clearance between the edge of the gauge wheel tire and the side of the planter's disk opener.

Our conclusion is that the rubber compound in gauge wheel tires has been has been stiffened to make the tires more resistant to damage in no-till conditions. Maybe the design of the bead area on the steel rims has been changed. Whatever the reason, it's a time-consuming and therefore potentially expensive challenge to change tires on gauge wheels.

Bottom line: until I figure out a better, faster, less frustrating way to replace gauge wheel tires, I'm installing new gauge wheels that come with new tires. I can do that in 10 minutes or less, and the customer ends up with a new tire, new wheel, new bearing and a lot lower labor charge so that it all equals out to about what it would cost for me to bludgeon one of those %!#@! new tires onto an old, worn wheel and bearing assembly.

So, it can be boring on the farm this time of year, and a trip to town is often a welcome break. In case you need an excuse to make that trip, here are some sure-fire ways to damage batteries in farm equipment so you have to drive to town for new ones:

-Store them in below-zero temperatures at less than full charge. I don't fully understand the chemistry, but from personal experience know that the electrolyte in a well-charged battery is very resistant to freezing, while the electrolyte in discharged batteries will freeze. Fully frozen batteries are junk batteries because the pressure from the expanding ice either ruptures the battery's case or damages the plates inside.

-Connect an industrial-duty battery charger to a battery, set it to "boost," and leave it charging for half-day or more. "Boost" settings are "dumb" settings---the charger keeps pouring high amperage into the battery whether the battery can accept it or not. Overcharging a battery can kill it. Unless a battery charger is specifically designed to monitor and self-adjust charging rates, be very cautious about leaving chargers attached to batteries for more than a couple hours at high amperage settings.

-Lose your temper while trying to clean the battery clamps and terminals. Been there, done that myself. Trying to clean battery terminals in the back corner of the machine shed, with poor lighting so you can't see what you're doing, is a sure-fire way to light the fuse on a temper tantrum. Your hands are numb, you're fumbling with cold wrenches while wearing gloves, and it's tempting to start pounding, twisting and prying on the clamps and terminals to get them apart. Plastic battery cases are more brittle when cold so it's possible to crack the case if you pry or pound on it. Rough twisting or prying of the cable clamps can dislodge/crack the junction between the top of the case and the battery post. Batteries are tough but they're not indestructible.

Ultimately, prevention is the best cure to prevent damage to batteries. With big tractor batteries often priced at more than $200 each, it's worth a little patience to make sure they're fully charged before storage and kept charged during storage. If they need charged or boosted during cold weather, do it with discretion. And if things aren't going well on a miserably cold day while attempting to remove battery clamps and clean battery terminals, and you feel the urge to "remodel" the battery terminals or clamps with a big hammer...I recommend a 32-ounce ball peen hammer. Might as well enjoy yourself before you drive to town for a couple of those $200 batteries.